After a few minutes of thought, you determine that you should...
Swap with Rufus (your golden retriever)
Your dog sounds like the best place to start. That way you won't have to worry about explaining it someone, and then convincing them to do it. You decide this is the perfect way to give it a shot, and run upstairs to get Rufus. You open your bedroom door and call for Rufus. A few seconds of waiting and Rufus comes trotting into your room to greet you. You quickly give him attention and shut the door behind him. Pulling open the bookshelf, you begin to descend and call for Rufus to follow you. He follows close behind, contently panting away as he trots down the steps. When you reach the bottom, you guide him over to one of the pods and close him inside. Confused and concerned, he whines after a moment and scratches at the inside of the metal container
"I know buddy, you'll be okay, I promise. Give me just a minute okay boy?"
He continues to whine, but quieter this time. He may not fully understanding what you're saying, but he senses in your soothing tone that everything will be okay. You walk over to the terminal and look at the dial. It currently read ten seconds, and you suppose that should be plenty of time to get to the pod and close it behind you. Taking a deep breathe, you press the button
Ten... nine...
You dash towards the pod and step inside. The cold metal surrounds you on all sides, making you feel just a little bit nervous
Eight... Seven... Six...
You quickly close the door behind you, and think about what you're doing. Are you actually doing this? Will it even work?
Five... Four...
You take a few deep breaths, but they only heighten your anxiety. Maybe you shouldn't be doing this... you should test it on something else first, something less important. What if something goes wrong? What if...
Three... Two... One
A low whirring sound begins to fill the room. The pods lock and you realize there's no turning back now. The whirring continues, and it seems to build upon itself, slowly gaining volume and speed as it continues. Getting more nervous by the second, you start to panic. What if it does work, but you can't switch back? What if you get trapped because the door never unlocks itself? What if-
Suddenly, the world around you explodes in light and sound. You're blinded by an immense white light that you can see through closed eyes, and a loud ringing fills your ears. They move past your senses and full your head completely, the light and sound filling all of your being
Then, just as suddenly, you faint
After a while of sleeping on the metal floor, you slowly wake up to see the giant pod door wide open. You blink a few times, not sure you completely remember what had happened. You slowly stand up and stumble your way out of the pod. Your mind is foggy, and everything feels just a little wrong, but you don't understand why. Everything feels the way it always should, and you can't put your paw on it...
Wait...
You look down to see a pair of golden fur-covered paws spanning from the floor to your golden fur-covered chest. Something about them... felt weird... but you couldn't place why it felt weird, it just... did?
You shake your head to clear it, your huge ears flopping wildly against the sides of your head as always. You slowly pad over to the staircase and begin to make your way up the stairs when a low groaning sound comes from behind you. You quickly turn to see... Marcus
Marcus was lying on the floor of the second pod, sleeping deeply and unmoving. Your canine jaw drops as realization suddenly dawns on you. You look down again at your front paws and then turn to see you've been walking on all fours this whole time. You also see your new tail sticking up in surprise, and after thinking about it you can feel it too. It's the strangest feeling, like having a spine that just keeps going and going past your waist. A shocked curse instinctively leaves your brain, only to be translated into a loud bark from your new snout. Your eyes cross as you look at the new muzzle, some of it blocking part of your usual field of view. You can't believe what just happened. You're Rufus! You're a golden retriever! And that means Rufus is...
You look back at Marcus, your prior self, sleeping on the floor. You think about the other side of the situation that you hadn't thought of before. Not only are you in Rufus's body, but now he's in yours! What's he going to do in your body? What problems is he going to get himself into? He doesn't even know how to speak! Or at least you don't think he does. You walk over to him, almost feeling mentally uncomfortable with how natural your four-legged stance feels and how easily you slip into the movement. You push the thought aside for now, as you have to do something with the dog in a boy's body. In your body
You reach Rufus, in your old body, and think about what to do with him. You can't let him go wandering around upstairs in your body messing things up. You have to do something about it. You decide to...